<?xml version="1.0" encoding="utf-8"?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Drag and drop and horizontal scrolling: dropping block element onto canvas inside scrollable container</title>
<style type="text/css">
div[draggable]
  {width:20px;
  height:20px;
  background-color:green;}
p + div
  {height:150px;
  width:100px;
  overflow-x:scroll;}
canvas
  {display:block;
  margin-left:100px;}
</style>
<script type="application/ecmascript">
function paint(color)
  {var canvas = document.querySelector('canvas'),
  c = canvas.getContext('2d');
  c.fillStyle = color;
  c.beginPath();
  c.moveTo(0,0);
  c.lineTo(100,0);
  c.lineTo(100,100);
  c.lineTo(0,100);
  c.closePath();
  c.fill();}
function start(event)
  {event.dataTransfer.effectAllowed = 'copy';
  event.dataTransfer.setData('text/plain', 'green');}
</script>
</head>
<body onload="paint('gray')">
<div draggable="true" ondragstart="start(event)"/>
<p>You should be able to drag green box above to the gray canvas at the right edge of scrollable container (dragging towards the right edge triggers scrolling). Canvas should be repainted to match dropped color.</p>
<div>
  <canvas width="100" height="100" ondragenter="event.preventDefault()" ondragover="return false" ondrop="paint(event.dataTransfer.getData('text/plain'))">Canvas</canvas>
</div>
</body>
</html>
